The present invention relates to agricultural sprayers of pressurized liquids and more particularly concerns such a sprayer in which the liquid is agitated and its pressure controlled.
Pressurized discharge of various types of liquid insecticides, fertilizers, herbicides and other agricultural type treatment liquid has been accomplished by directly pressurizing a pressure vessel that is mounted within a portable liquid container, with a pump also connected to the container and pressure vessel. Liquid is drawn from the container, caused to flow under pressure into the pressure vessel and is sprayed therefrom under control of a spraying valve. Efficient spraying of agricultural insecticides, herbicides, and the like, requires control of the amount of insecticide dispensed as well as regulation of spraying pressure. All manufacturers of spraying chemicals recommend preferred use rates for efficient application of the chemicals. These rates specify the amount of chemical to be used per acre. However, the recommended rates can be met only if the spraying equipment is able to control the pressure output, the rate of output flow and the strength of the solution. For some materials, solution strength depends on the amount of non-soluble but wettable particles maintained in suspension within the solution. In such suspensions, agitation is required to minimize precipitation of solid particles so as to maintain solution strength.
Neither efficient pressure regulation nor practical agitation of suspensions of wettable powders has heretofore been available in portable agricultural sprayers.
Accordingly, it is an object of the present invention to provide for pressure regulation and/or agitation in the spraying of agricultural liquids.